Matt Damon is set to make his directorial debut in a drama co-written by John Krasinski.The Hollywood heavyweight, who has been guided by top directors including Martin Scorsese and Steven Soderbergh during his career, has previously spoken of his desire to step behind the camera one day, declaring, "I've been treating the last 12 years like a film school." He has now landed his first project after writing a script with The Office star Krasinski. Damon will star as a salesman in a small town in the as-yet-untitled drama, according to The Hollywood Reporter.